The increased amount of Photovoltaic (PV) power installed into the power system every year places this renewable way of producing electricity on the third position in the renewable sources hierarchy after hydro and wind solutions. Having significant levels of renewable power penetration into the system led to stability concerns of the entire system affecting its reliability and availability. In consequence system operators such as the European Network of Transmission System Operators for Electricity (ENTSO-E) had an immediate response imposing strict operating regulations in order to keep the system stable and harmonize the operation of the renewable plants with the entire system. For this purpose valid grid benchmarks such as IEEE 12 bus system for High Voltage (HV) and Cigré benchmark cell model for Medium Voltage (MV) have to be developed, tested together and prove that in the future power system with large PV penetration levels on every level, the system continues to be reliable and redundant.